I'm not a native Spanish speaker, but I imagine, the difference in usage is similar to the difference in English between "I want" (quiero) and "I would like" (quisiera). One is less blunt and more polite.
Quisiera is the subjunctive imperfective form of querer. The subjunctive form is used to talk about desires, doubts, wishes, conjectures, and possibilities. This helps a lot. https://www.spanishdict.com/guide/subjunctive-vs-indicative-in-spanish
Altough this is an excellent link it is not relevant to the use of quisiera in this sentence. The rules you are referring to relate to the verbs in subordinate clauses. In this sentence there is no SC.
The indicative mode, NOT the subjunctive, is normally used to express YOUR OWN desires, wants or wishes.
The subjunctive mode is use in the subordinate clause when talking about what you or someone else wants a third party to do. This sentence involves only one party, there is no subordinate clause, so the most common and acceptable thing is to use the indicative. Quisiera is only use to be super-polite, it is in no way required by the rules of subjunctive usage.
I have also heard the "would likes" are much less common. I heard that specifically about Spain, but took it to mean Spanish in general. Someone else on here called it ~"overly formal"
Correct. You can also use "me gustaria..." for I would like, which is the usage I'm familiar with from travels in south america. As in "Me gustaria un libro"
"Quiero una cerveza" means "I want a beer," whereas "Quisiera una cerveza" means "I would like a beer." Quisiera is more formal and more polite.
Strange as it may seem, the most frequent verb used fe ordering a beer is poner, in either the informal imperative or as a question. Literally speaking, it say "Put me a beer" I think of it as the Spanish ways of saying "Gimme a beer" :)
By the way, at least according to a Columbian show (La Niña) that I watched recently, the most common way of ordering something at a bar or a food truck is with the verb regalar - to give a gift. ¿Me regalas una cerveza?
Ver respuesta de "Adailek", es correcta y puedo agregar que "quisiera" también podría ser algo que uno desea.
I wrote "I want a beer" and duo said the correct answer was "I fancy a beer" I fancy a lot of things but not beer. I guess the same Duo that wrote that was going to get an "after" later
Regional preferences and varying contexts influences this choice. Some people in Spain for example say that me gustaría is used more for true dreams or aspirations not for ordering food in a restaurant.
It tells me the answer is not "I want a beer" but "I fancy a beer" I don't know the subtleties of Spanish but I do know we do not say we fancy a beer in the United States!
To say "I fancy something" is very English (as in the UK). It equates best to "I would like (please)" rather than "I want".
Why do some of the 'quisiera...' answers require 'yo' afterwards for 'I would like..' but not in this instance?
I haven't seen yo follow the verb on here. If it's grammatically correct, I didn't know it was. But yo preceding the verb is optional. "Quisiera" can mean any of these:
"I would like"
"He/She would like"
"You (formal) would like"
See the conjugations here under Subjunctive > Imperfect. Note that imperfect 2 conjugations mean the same but are less common.
I thought that when the verb conjugation was ambiguous, and the subject wasn't obvious from context, you were supposed to specify the pronoun to resolve the ambiguity. That wouldn't be necessary if I were sitting alone at a table, but if I were ordering with my wife I would be inclined to say "Yo quisiera una birra y mi esposa quisiera agua sin gas." (She hates beer.)
It that not correct?
That assumption is very correct. But for any sentence on here, we don't know if there's ambiguity or not.
EDITED: BryceSpringfield corrected me on this post. Please ignore my comment here and refer to him below.
I'm not sure if I'm understanding you correctly. I don't remember seeing any sentences that say "Quisiera yo..." but I have seen a few say "Yo quisiera...".
THE FOLLOWING IS MY ORIGINAL COMMENT, BUT IS NOT TRUE: Because "quisiera" is specific to the first person, "yo" is implied and not necessary. It is still fine to say "Yo quisiera," especially if you want to emphasize the subject. I don't think "yo" should be required by DuoLingo in these types of sentences.
Si digo: Yo quisiera caminar o quisiera caminar es lo mismo en Español porque estoy hablando de mí. "Quisiera tomar una cerveza" o "yo quisiera" ..... o "me gustaría tomar una"... o "a mi me gustaría tomar ".... es lo mismo. Pero si estoy hablando de otra persona tengo que decir: "Él quisiera una" .... o " A él le gustaría una cerveza..."
Why is the subjunctive used? Is it kind of like "I may like" or "I may want"?
Subjunctive is NOT required in this sentence in Spanish except as one option to express courtesy similar to to English "I would like" instead of "I want"
Wrong, when expressing your own hope for some object you can use the indicative. When you express a hope that someone else does something then you use the subjunctive for the verb that involves their possible action.
You CAN use the imperfect subjunctive or the conditional as a way of being super polite, but it is usually not necessary.
I wrote: I would like to have a beer.
DL did not accept it and proposed instead: "You used the wrong word. I would like one a beer." That sounds really weird to me - question to English speakers: is that an option?
I wrote "I am wanting a beer" ...denotes speakers feeling, not blunt or impolite. I've said it many times (in America) to show my "taste / choice"
According to this: https://www.123teachme.com/spanish_verb_conjugation/querer AND this: http://www.spanishdict.com/conjugate/querer
"quisiera" is subjunctive imperfect meaning "I wanted" or "I was wanting." One could argue (or not) whether "I was wanting" = "I would like." That said, "I would want" is something entirely different. I'm no grammarian, but I wonder if DL isn't doing us all a disservice by introducing these moods. See this for more: https://www.spanishdict.com/guide/subjunctive-vs-indicative-in-spanish
Those general rules about the subjunctive only apply for when they are used in a subordinate clause, like
- Si quisiera ese sombrero, lo compraría. - If I wanted that hat, I would have bought it.
But here it's one of the fancy main-clause uses. The imperfect subjunctive form can be used for polite expressions, which are reflected with the conditional "would" in English.
Imperfect subjunctive of querer. Don't bother too much about understanding that verb form it in this context. It's a polite expression.
Because that's not the same meaning. Your sentence is like a conditional. "If I were at the bar, I would want a beer." In the Spanish sentence, the person actually wants a beer now.
That would match better with the actual conditional form, "Querría una cerveza."